We all appreciate that wind is expected to make a substantial contribution to a more secure and sustainable energy system. However, electricity generation from the technology is constrained by the varying availability of the resource. One possible solution is Variable Renewable Energy (VRE) – the ultimate cost-effective combination of wind and solar power. PES looks at the latest top line research.
Fluctuating natural conditions can make it challenging to maintain the necessary balance of electricity supply and consumption at all times. Consequently, the cost-effective integration of VRE has become a pressing challenge for the energy sector.
Based on a thorough assessment of flexibility options currently available for VRE integration, a major finding is that large shares of VRE (up to 45% in annual generation) can be integrated without significantly increasing power system costs in the long run. However, cost-effective integration calls for a system-wide transformation. Moreover, each country may need to deal with different circumstances in achieving such a transformation.
The interaction of VRE and other system components determine opportunities and challenges of integration. The difficulty (or ease) of increasing the share of variable generation in a power system depends on two main factors:
Firstly, the properties of wind and PV generation, in particular the constraints that weather and daylight patterns have on where and when they can generate. Secondly, the flexibility of the power system into which VRE is integrated and the characteristics of the system’s electricity demand.
For example, where good wind and solar resources are far away from demand centres, it can be costly to connect them to the grid. On the other hand, where sunny periods coincide with high electricity demand, solar PV generation can be integrated more easily.
The interaction between both factors differs from system to system. As a result, the economic impacts of VRE also depend on the specific context. However, on both sides only a limited number of properties determine the positive and negative aspects of integration. This allows identifying best practice principles that apply in a wider range of circumstances.